Method and apparatus for data reception

Abstract

Method and apparatus for data reception are provided, retrieving digital values transmitted through a cable. In a data receiver, an equalizer equalizes an input signal based on a boost value to generate an equalized signal, and a data extractor samples the equalized signal to extract output values from each symbol period. The data extractor detects signal quality of the equalized signal to adjust the boost value accordingly. An optimal time point is detected within one symbol period where an output value is an ensured valid, and variation rate of the optimal time point is counted as an inverse indicator of the signal quality.

Description

CROSS REFERENCE TO RELATED APPLICATIONS[0001]This application claims the benefit of U.S. Provisional Application No. 60 / 916,581 filed on May 8, 2007.BACKGROUND OF THE INVENTION[0002]1. Field of the Invention[0003]The invention relates to high speed cable links, and in particular, to adaptive data reception for signals transferred through a cable.[0004]2. Description of the Related Art[0005]FIG. 1 shows an eye diagram. Cables or conductive wires are widely used media for signal transmission, in which digital data are sequentially transmitted in symbol form. A symbol may be an application dependent waveform having predetermined amplitude and duration. For example, in FIG. 1, a symbol generated at the transmitter end may have amplitude VS and data period TP. During the data period TP, a duration between time points ta and tb is referred to as the hold time TH, whereas the others setup time TS. A valid symbol value is only acquirable during the hold time TH where the symbol amplitude is...

AI Technical Summary

Benefits of technology

The adaptive equalizer effectively improves signal quality by dynamically adjusting the boost value, enhancing data extraction accuracy and reducing data jitter, thereby improving the efficiency of signal transmission across varying cable conditions.

Problems solved by technology

Practically, however, a cable is equivalent to a low pass filter that reduces signal quality.

Thus, a distorted symbol may cause a so-called data jitter, reducing the possibility to correctly sample an output value.

As the available hold time TH′ is shortened, duration of uncertainty is increased and implementation of an accurate sampling mechanism becomes more difficult.

The input signal #DIN may be distorted when passing through the cable, having data jitter that is difficult to reacquire output values therefrom.

Under equalization, in particular, often causes severe data jitter that greatly impacts efficiency of signal transmission.

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